Ali Alhousseini

Kinetics of lipopolysaccharide clearance by Kupffer and parenchyma cells in perfused rat liver.

We studied the kinetics of [3H]lipopolysaccharide ([3H]LPS) (endotoxin) binding to Kupffer cells and hepatocytes at the level of the microtubular system after treatment with gadolinium chloride (GdCl(3)) and colchicine. Liver perfusion in Sprague-Dawley rats involves both portal vein and thoracic inferior vena cava cannulations as inlet and outlet, respectively. The subhepatic inferior vena cava is ligated to prevent perfusate leakage. Buffer containing 2% serum and [3H]LPS is administered at 1 ml/min and collected for 50 min. Rate constants for hepatocellular clearance of [3H]LPS in controls, colchicine-treated rats, GdCl(3)-treated rats, and colchicine plus GdCl(3)-treated rats are assessed using a simplified mathematical model. Forward-binding, reversal-binding, residency time, and influx rate constants are estimated. Results show that in GdCl(3)-treated rats, the hepatocytes effectively clear endotoxin from the circulation, and its ultimate binding affinity at the hepatocyte site is somewhat reduced compared to the Kupffer cells. In colchicine-treated rats, the disruption of the microtubule network altered [3H]LPS binding with Kupffer cells, suggesting that the microfilament-microtubular network also affects Kupffer cell function. Simultaneous treatments with colchicine and GdCl(3) increased the influx rate constant, suggesting that the compiled morphological alterations up-regulated endotoxin clearance by the liver, as indicated by a drastic increase in cellular vacuolation. In conclusion, the kinetics of the trafficking process of [3H]LPS clearance are regulated by apical-sinusoidal endocytotic and canalicular routes.

Are amniotic fluid neutrophils in women with intraamniotic infection and/or inflammation of fetal or maternal origin?

Background Neutrophils are the most abundant white blood cells found in the amniotic cavity of women with intraamniotic infection and/or inflammation. The current belief is that these neutrophils are of fetal origin. However, abundant neutrophils have been found in the amniotic fluid of women with a severe acute maternal inflammatory response but without a severe fetal inflammatory response in the placenta, suggesting that these innate immune cells can also be of maternal origin or a mixture of both fetal and maternal neutrophils. Objective We sought to investigate the origin of amniotic fluid neutrophils from women with intraamniotic infection and/or inflammation and to correlate these findings with acute histologic maternal and fetal inflammatory responses in the placenta. Study Design Amniotic fluid was collected from 15 women with suspected intraamniotic infection and/or inflammation (positive microbiological cultures and/or interleukin‐6 concentrations ≥2.6 ng/mL). Amniotic fluid neutrophils were purified by fluorescence‐activated cell sorting, DNA was extracted, and DNA fingerprinting was performed. DNA fingerprinting was also performed in the umbilical cord and maternal blood DNA. Fluorescence in situ hybridization was assayed in women with male neonates. Blinded placental histopathological evaluations were conducted. Results First, DNA fingerprinting revealed that 43% (6/14) of women who underwent a single amniocentesis had mostly fetal neutrophils in the amniotic fluid. Second, DNA fingerprinting showed that 36% (5/14) of the women who underwent a single amniocentesis had predominantly maternal neutrophils in the amniotic fluid. Third, DNA fingerprinting indicated that 21% (3/14) of the women who underwent a single amniocentesis had an evident mixture of fetal and maternal neutrophils in the amniotic fluid. Fourth, DNA fingerprinting revealed that a woman who underwent 2 amniocenteses (patient 15) had fetal neutrophils first, and as infection progressed, abundant maternal neutrophils invaded the amniotic cavity. Fifth, fluorescence in situ hybridization confirmed DNA fingerprinting results by showing that both fetal and maternal neutrophils were present in the amniotic fluid. Sixth, most of the women who had predominantly amniotic fluid neutrophils of fetal origin at the time of collection delivered extremely preterm neonates (71% [5/7]). Seventh, all of the women who had predominantly amniotic fluid neutrophils of maternal origin at the time of collection delivered term or late preterm neonates (100% [6/6]). Eighth, 2 of the women who had an evident mixture of fetal and maternal neutrophils in the amniotic fluid at the time of collection delivered extremely preterm neonates (67% [2/3]), and the third woman delivered a term neonate (33% [1/3]). Finally, most of the women included in this study presented acute maternal and fetal inflammatory responses in the placenta (87% [13/15]). Conclusion Amniotic fluid neutrophils can be either predominantly of fetal or maternal origin, or a mixture of both fetal and maternal origin, in women with intraamniotic infection and/or inflammation. The findings herein provide evidence that both fetal and maternal neutrophils can invade the amniotic cavity, suggesting that both the fetus and the mother participate in the host defense mechanisms against intraamniotic infection.

Amniotic fluid neutrophils can phagocytize bacteria: A mechanism for microbial killing in the amniotic cavity

Neutrophils are capable of performing phagocytosis, a primary mechanism for microbial killing. Intra‐amniotic infection is characterized by an influx of neutrophils into the amniotic cavity. Herein, we investigated whether amniotic fluid neutrophils could phagocytize bacteria found in the amniotic cavity of women with intra‐amniotic infection.

The immunophenotype of amniotic fluid leukocytes in normal and complicated pregnancies

The immune cellular composition of amniotic fluid is poorly understood. Herein, we determined: 1) the immunophenotype of amniotic fluid immune cells during the second and third trimester in the absence of intra‐amniotic infection/inflammation; 2) whether amniotic fluid T cells and ILCs display different phenotypical characteristics to that of peripheral cells; and 3) whether the amniotic fluid immune cells are altered in women with intra‐amniotic infection/inflammation.

Intrahepatic Cholestasis of Pregnancy Leading to Severe Vitamin K Deficiency and Coagulopathy

Intrahepatic cholestasis of pregnancy is seldom associated with significant vitamin K deficiency. We report a case of a 16-year-old primigravid patient at 24 weeks and 3 days of gestation who presented with pruritus, hematuria, and preterm labor. Laboratory work-up showed severe coagulopathy with Prothrombin Time (PT) of 117.8 seconds, International Normalized Ratio (INR) of 10.34, and elevated transaminases suggestive of intrahepatic cholestasis of pregnancy. Her serum vitamin K level was undetectable (<0.1 nMol/L). Initial therapy consisted of intramuscular replacement of vitamin K and administration of fresh frozen plasma. Her hematuria and preterm labor resolved and she was discharged. She presented in active labor and delivered at 27 weeks and 1 day. Her bile acids (93 μ/L) and INR (2.32) had worsened. She delivered a male infant, 1150 grams with Apgar scores 7 and 9. The newborn received 0.5 mg of intramuscular vitamin K shortly after delivery but went on to develop bilateral grade III intraventricular hemorrhages by day 5. Intrahepatic cholestasis in pregnancy and nutrition issues were identified as the main risk factors for the severe coagulopathy of this patient. This case underlines the importance of evaluation of possible severe coagulopathy in patients with intrahepatic cholestasis of pregnancy in order to avoid serious maternal or fetal adverse outcomes.

Use of Fluorescence In Situ Hybridization Technology to Explain a Confusing Case of Vasa Previa

Vasa previa is defined as unprotected fetal vessels coursing within the membranes overlying or in close proximity to the cervix. The incidence is approximately 1 per 1300 to 2500 singleton pregnancies, with major fetal and neonatal morbidity and mortality occurring. The rate of vasa previa in twin pregnancies is higher, estimated at 1 per 135 cases. Velamentous cord insertion and a succenturiate lobe are the conditions reported to lead to vasa previa. Vasa previa in the absence of a velamentous cord or succenturiate lobe has not been reported. We describe a case of antenatally identified vasa previa in a dichorionic twin gestation with 2 early separated placental masses. Although there are speculations in the literature that vascular anastomoses can occur between dichorionic placentas, they have been reported only under the circumstances in which the placentas are fused. After delivery, macroscopic examination of the placentas in our case seemed to confirm this event of separate placentas without the evidence of the presence of velamentous cord insertion or a succenturiate lobe until fluorescence in situ hybridization was used to clarify the findings. A 36-year-old woman, gravida 2, para 0010, presented at 9 weeks with an ultrasound-confirmed diamniotic dichorionic pregnancy. Ultrasound scanning at 19 weeks’ gestation showed twin A to be a female fetus with a posterior placenta. Twin B was a male fetus with a separate anterior placenta (Figure 1A). A follow-up transvaginal ultrasound scan at 22 weeks’ gestation suggested the diagnosis of vasa previa (Figure 1B). The free fetal vessel appeared to be communicating between the 2 separate placental masses, traversing across the endocervical canal. These ultrasound findings persisted at 27 and 34 weeks’ gestation. At 34 weeks 2 days, the patient

Incarcerated Uterus Presenting as Short Cervix and Placenta Previa

Introduction Incarcerated uterus is a rare complication of pregnancy, usually associated with retroversion. Case A 26-year-old woman presents at 19 4/7 weeks for evaluation of a short cervix and placenta previa. On ultrasound scan, the placenta was considered previa and the cervix was not visualized. The cervix was not identified by pelvic examination and the presumptive diagnosis of short cervix was done. The patient was followed up closely and remained asymptomatic. Retrospective analysis of the ultrasound images showed a retroverted uterus with an elongated cervix compressed towards the anterior vaginal wall. At 26 weeks of gestation, ultrasound showed a cervical length of 41 mm and a fundal placenta and the diagnosis of spontaneous correction of an incarcerated uterus was made. The patient had an uncomplicated vaginal delivery at 39 3/7 weeks. Comment Identification and close follow-up of incarcerated uterus may potentially help in avoiding serious obstetrical and surgical complications.

Umbilical Artery Thrombosis with Associated Acute and Severe Fetal Growth Restriction and Transient Severe Protein S Deficiency: Report of a Case with Prenatal Ultrasound Diagnosis Allowing for Timely Intervention and Good Outcome

Background Thrombosis of one of the umbilical arteries can be associated with adverse pregnancy outcomes such as stillbirth and severe intrauterine growth restriction (IUGR). Case A 21-year-old gravida 1 patient, with a history of 3-vessel cord at 20 weeks, presented at 29 weeks with a single umbilical artery. The estimated fetal weight measurements at 26 weeks, 29 weeks, and 31 weeks were at the 27th percentile, the 26th percentile, and less than the 5th percentile, respectively. At 33 weeks, amniotic fluid index became abnormal at 2.3 cm and fetal heart tracing revealed spontaneous prolonged decelerations, and a cesarean delivery was performed. Placental pathology showed thrombosis of one of the umbilical arteries. At birth, a transient protein S deficiency was detected (activity 13%) and resolved at two months of age (activity 66%). The baby had an uneventful clinical course since birth. Conclusion The recognition of reduction of umbilical arteries from two to one allowed for timely intervention with good outcome in this case. Thrombosis of umbilical vessels may be associated with a deficiency in coagulation proteins such as protein S.